Topband: 160m at solar max
Bill Tippett
btippett at alum.mit.edu
Tue Mar 9 07:39:23 EST 2004
K9LA wrote:
>Without this influence
from the high latitude ionosphere (unlike those of us poor souls farther
north), his log data tends to confirm that the quiet (undisturbed)
nighttime ionosphere in terms of absorption isn't all that different
between solar max and solar min.
I disagree Carl. Your data did not include anything from
the solar minimum years (95-97). I'm at 35 N and Tom is at 33 N,
and I can tell you that the conditions in the 95-97 period were
simply MUCH better than they are now. Signal strengths from JA's
would actually sometimes be S9 on the meter, and signals from EU
would be well over S9, and so strong that you could work lots of
Russians on SSB. They just aren't that strong now.
Here's NOAA data showing historical average flux (middle graph)
and average Ap indices (bottom graph):
http://www.sec.noaa.gov/SolarCycle/
As the graphs show, some of the best conditions are actually just
after the new cycle begins, when geomagnetic activity (Ap) is at its
lowest (1996-97 on the bottom graph above).
Just for a little more data from all areas of the world, here
are when current 160 records were set in the CQ WW CW by Zone:
1974 - 22 <- cycle low
1977 - 38
1978 - 32
1985 - 06, 09, 10, 23, 29 <- cycle low
1986 - 13
1990 - 25
1993 - 35
1995 - 01, 02, 03, 04, 14, 15, 19, 21, 40 <- cycle low
1996 - 08, 11, 26, 27, 30, 39
1997 - 07, 16, 31, 33
1998 - 05
1999 - 20
2000 - 17, 18
2002 - 28
NONE - 12, 24, 34, 36, 37 (opportunity!)
Source: http://cqww.com/zone_c.htm
It seems fairly clear to me that every area of the world benefits
from the low absorption and low geomagnetic activity which we see
at cycle bottoms and a year or two after, independent of latitude.
http://www.spacew.com/swim/bigstorm.html
73, Bill W4ZV
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